Projectile points, some in the fluted style called "Clovis" and others in the parallel-flaked style shown here, were made by the early hunters who followed retreating ice sheets northward through the Mississippi Valley. They were used with spears or javelins. A few such points, chipped from hard, glassy rock, have been found at scattered places in this region. Most Paleo-Indian campsites, especially those along rivers, are buried beneath many feet of sand and silt.